/**
 * @license Copyright (c) 2003-2023, CKSource Holding sp. z o.o. All rights reserved.
 * For licensing, see LICENSE.md or https://ckeditor.com/legal/ckeditor-oss-license
 */
/**
 * @module engine/view/document
 */
import DocumentSelection from './documentselection';
import { Collection } from '@ckeditor/ckeditor5-utils';
import type { StylesProcessor } from './stylesmap';
import type RootEditableElement from './rooteditableelement';
import type DowncastWriter from './downcastwriter';
declare const Document_base: import("@ckeditor/ckeditor5-utils").Mixed<{
    new (): import("@ckeditor/ckeditor5-utils").Observable;
    prototype: import("@ckeditor/ckeditor5-utils").Observable;
}, import("@ckeditor/ckeditor5-utils").Emitter>;
/**
 * Document class creates an abstract layer over the content editable area, contains a tree of view elements and
 * {@link module:engine/view/documentselection~DocumentSelection view selection} associated with this document.
 */
export default class Document extends Document_base {
    /**
     * Selection done on this document.
     */
    readonly selection: DocumentSelection;
    /**
     * Roots of the view tree. Collection of the {@link module:engine/view/element~Element view elements}.
     *
     * View roots are created as a result of binding between {@link module:engine/view/document~Document#roots} and
     * {@link module:engine/model/document~Document#roots} and this is handled by
     * {@link module:engine/controller/editingcontroller~EditingController}, so to create view root we need to create
     * model root using {@link module:engine/model/document~Document#createRoot}.
     */
    readonly roots: Collection<RootEditableElement>;
    /**
     * The styles processor instance used by this document when normalizing styles.
     */
    readonly stylesProcessor: StylesProcessor;
    /**
     * Defines whether document is in read-only mode.
     *
     * When document is read-ony then all roots are read-only as well and caret placed inside this root is hidden.
     *
     * @observable
     */
    isReadOnly: boolean;
    /**
     * True if document is focused.
     *
     * This property is updated by the {@link module:engine/view/observer/focusobserver~FocusObserver}.
     * If the {@link module:engine/view/observer/focusobserver~FocusObserver} is disabled this property will not change.
     *
     * @readonly
     * @observable
     */
    isFocused: boolean;
    /**
     * `true` while the user is making a selection in the document (e.g. holding the mouse button and moving the cursor).
     * When they stop selecting, the property goes back to `false`.
     *
     * This property is updated by the {@link module:engine/view/observer/selectionobserver~SelectionObserver}.
     *
     * @readonly
     * @observable
     */
    isSelecting: boolean;
    /**
     * True if composition is in progress inside the document.
     *
     * This property is updated by the {@link module:engine/view/observer/compositionobserver~CompositionObserver}.
     * If the {@link module:engine/view/observer/compositionobserver~CompositionObserver} is disabled this property will not change.
     *
     * @readonly
     * @observable
     */
    isComposing: boolean;
    /**
     * Post-fixer callbacks registered to the view document.
     */
    private readonly _postFixers;
    /**
     * Creates a Document instance.
     *
     * @param stylesProcessor The styles processor instance.
     */
    constructor(stylesProcessor: StylesProcessor);
    /**
     * Gets a {@link module:engine/view/document~Document#roots view root element} with the specified name. If the name is not
     * specific "main" root is returned.
     *
     * @param name Name of the root.
     * @returns The view root element with the specified name or null when there is no root of given name.
     */
    getRoot(name?: string): RootEditableElement | null;
    /**
     * Allows registering post-fixer callbacks. A post-fixers mechanism allows to update the view tree just before it is rendered
     * to the DOM.
     *
     * Post-fixers are executed right after all changes from the outermost change block were applied but
     * before the {@link module:engine/view/view~View#event:render render event} is fired. If a post-fixer callback made
     * a change, it should return `true`. When this happens, all post-fixers are fired again to check if something else should
     * not be fixed in the new document tree state.
     *
     * View post-fixers are useful when you want to apply some fixes whenever the view structure changes. Keep in mind that
     * changes executed in a view post-fixer should not break model-view mapping.
     *
     * The types of changes which should be safe:
     *
     * * adding or removing attribute from elements,
     * * changes inside of {@link module:engine/view/uielement~UIElement UI elements},
     * * {@link module:engine/controller/editingcontroller~EditingController#reconvertItem marking some of the model elements to be
     * re-converted}.
     *
     * Try to avoid changes which touch view structure:
     *
     * * you should not add or remove nor wrap or unwrap any view elements,
     * * you should not change the editor data model in a view post-fixer.
     *
     * As a parameter, a post-fixer callback receives a {@link module:engine/view/downcastwriter~DowncastWriter downcast writer}.
     *
     * Typically, a post-fixer will look like this:
     *
     * ```ts
     * editor.editing.view.document.registerPostFixer( writer => {
     * 	if ( checkSomeCondition() ) {
     * 		writer.doSomething();
     *
     * 		// Let other post-fixers know that something changed.
     * 		return true;
     * 	}
     * } );
     * ```
     *
     * Note that nothing happens right after you register a post-fixer (e.g. execute such a code in the console).
     * That is because adding a post-fixer does not execute it.
     * The post-fixer will be executed as soon as any change in the document needs to cause its rendering.
     * If you want to re-render the editor's view after registering the post-fixer then you should do it manually by calling
     * {@link module:engine/view/view~View#forceRender `view.forceRender()`}.
     *
     * If you need to register a callback which is executed when DOM elements are already updated,
     * use {@link module:engine/view/view~View#event:render render event}.
     */
    registerPostFixer(postFixer: ViewDocumentPostFixer): void;
    /**
     * Destroys this instance. Makes sure that all observers are destroyed and listeners removed.
     */
    destroy(): void;
    /**
     * Performs post-fixer loops. Executes post-fixer callbacks as long as none of them has done any changes to the model.
     *
     * @internal
     */
    _callPostFixers(writer: DowncastWriter): void;
}
/**
 * Document PostFixer.
 *
 * @see module:engine/view/document~Document#registerPostFixer
 */
export type ViewDocumentPostFixer = (writer: DowncastWriter) => boolean;
/**
 * Enum representing type of the change.
 *
 * Possible values:
 *
 * * `children` - for child list changes,
 * * `attributes` - for element attributes changes,
 * * `text` - for text nodes changes.
 *
 * @typedef {String} module:engine/view/document~ChangeType
 */
export type ChangeType = 'children' | 'attributes' | 'text';
/**
 * Event fired whenever document content layout changes. It is fired whenever content is
 * {@link module:engine/view/view~View#event:render rendered}, but should be also fired by observers in case of
 * other actions which may change layout, for instance when image loads.
 *
 * @eventName ~Document#layoutChanged
 */
export type ViewDocumentLayoutChangedEvent = {
    name: 'layoutChanged';
    args: [];
};
export {};
